[GRASS-dev] Re: r.in.gdal: how to speed-up import with huge amount of bands?

[Hamish]

> It allocates way more RAM (2GB) but the speed remains exactly
> the same: 120 seconds per band.
> 
> > The original files are in netCDF format, I used gdalwarp to
> > generate GeoTIFF.
> > First I thought to write it out as 21550 files but didn't
> > find an option to do so.

gdal_translate can do that? e.g. see examples of extracting the
quality band into its own raster map from the MODIS grass wiki
page.

ncdump might be able do the same.

are the netCDF/geotiff pixel or band interleaved? if pixel there's
not much you can do to not read the whole file in. if band then
it should be (theoretically) pretty quick to fseek() to the right
part of the file.

other than that, split the job in 4 and borrow 3 other machines
for a week...


good luck,
Hamish